I have a DeWalt 3/8" drill I've enjoyed using the last half dozen years,
but it's Ni-Cad and I've already bought two batteries for it as they
have started deteriorating. Grrr. They aren't cheap. I wondered about
buying an Li Ion battery pack for it but couldn't find any, and I didn't
bother determining whether the existing Ni-Cad charger might have worked
properly with a Li Ion battery pack.

So, I remember Gregg mentioned he had some luck with Makita Li Ion
drills. I don't have any need for really heavy duty unit, and I have a
1/2" wall power drill, anyway. I ordered a Makita 12-volt 3/8" Li Ion
drill today with two batteries and a charger.

It better work out for me. Otherwise it is Gregg's fault.

Now, I have to figure out how to keep it properly charged when I'm not
using it, which is pretty much all of the time. I don't want to
overcharge the battery packs, which is probably what killed the ni-cads
in my DeWalt.